ALT Using chemical-shift scaling (an NMR pulse sequence), we have shown it possible to accurately shift-scale spectra to 2% of the original field strength, accounting for exchange and second-order effects. When applied to exchanging systems, it can be used to extract isothermal coalescence frequencies and rates (of potential interest to biomolecules etc.). It can also be combined with VTNMR to get closer to coalescence or obtain several coalescence points. This improves the accuracy of Eyring plots, significantly reducing the uncertainty of thermodynamic activation parameters. There is scope for further reduction of these uncertainties and application to heteronuclei.